8 Gigabyte Sandisk MicroSDHC Incompatibility

[Yann Droneaud]

Le jeudi 20 mai 2010 à 21:06 -0400, Vencabot Teppoo a écrit :
> Hello, community! This is my first time joining a mailing list, so
> excuse me if my netiquette leaves anything to be desired, and let me
> know.
> 

Hi,

I have a Kingston SDC4/4GB-2ADP : 4GB SHDC which shows write errors when
access are not aligned on a boundary. I've first suspect a problem with
the Freerunner has the problem only arise when booting from this SD
card.
But I've tested it latter with a USB card reader (Transcend M5) and
found problems when random reading/writing on a partition.
I've retried with 1MB aligned partitions and found that everything was
going well.

So aligning partition is not only a matter of performance, for some card
it's also a requirement.

To align partition with fdisk from util-linux use the following options:

c  - toggle msdos compatibility flag
u  - set unit to sectors instead of cylinder

See for example:
http://old.nabble.com/-ANNOUNCE--util-linux-ng-v2.17.1-td27685302.html

Regards.

-- 
Yann Droneaud